Azo dyestuffs of low solubility in water



2,980,666 AZO DYESTUFFS F LOW SOLUBILITY IN WATER Ernest Meriau, Bottmingen, and Bruno J. R.

Basel, Switzerland, assignors to Sandoz Ltd., Switzerland No Drawing. Filed June 9, 1958, Ser. No. 740,603 Claims priority, application Switzerland June 13, 1957 6 Claims. (Cl. 260-158) Nicolaus, Basel,

The present invention relates to a process for the pro duction of new azo dyestuffs which have low solubility in water and correspond to the general formula:

R stands for hydrogen, low molecular alkyl, low molecular hydroxyalkyl or low molecular alkoxyalkyl,

R for hydrogen, low molecular alkyl, low molecular hydroxyalkyl, low molecular alkoxyalkyl, aryl, cycloalkyl, or aralkyl,

R for hydrogen, low molecular alkyl or, together with R CH=CH-CH=CH,

R for hydrogen, low molecular alkyl or, together with R CH=CHCH=CH,

Y for hydrogen, halogen, a low molecular alkyl or alkoxy radical, the trifluoromethyl or trifluoroacetyl radical or an alkanoylamino radical with at most 18 carbon atoms,

R for a divalent aliphatic radical with 1 to 4 carbon atoms, 7

R for a hydroxyalkyl, dihydroxyalkyl, alkoxyalkyl, cy-

anoalkyl or acetoxyalkyl radical, the latter of which may be further substituted, or the difluoromethyl or trifluoromethyl radical, or the radical of a fluorinated cyanoalkyl, a carbalkoxyalkyl or a carbamic acid alkyl ester,

M for hydrogen, hydroxyl, an alkoxy radical, an acetoxy radical which may be further substituted or a carbamic acid alkyl ester radical, when n stands for the figure 1, or for a simple C-N linkage when n stands for the figure 2,

n for the figure 1 or 2, and

Z for hydrogen, methyl or methoxy or, together with N-CH -R and the adjacent benzene nucleus, a tetrahydroquinoline ring.

Especially valuable are the monoazo dyestufis which correspond to the formula CHz-CHrO-C O-Ra wherein R stands for hydrogen, methyl or phenyl,

R stands for methyl or phenylamino, and

R, stands for hydrogen, chlorine, methyl, acetylamino or propionylamino, V v

2,980,666 Patented Apr. 18, 1961 "ice and the monoazo dyestufis which correspond to the formula a s OH N-O S U rCHrRio WN N carom-0N wherein R stands for hydrogen, methyl or phenyl, and R stands for hydrogen, methyl, ethyl, hydroxy and acetoxy.

A number of the new, poorly water-soluble azo dyestuffs dye from aqueous dispersion polyamide fibers,

v e.g. nylon, Perlon (registered trademark), secondary N-OzS C-NH:

wherein R R R and R possess the meanings assigned I to them above, I

and coupling with 1 mole of a coupling component of the formula N 1 Rr-M lHrRgJ wherein R R M, X, Y and n possess the above-stated meanings.

Thevdiazo compounds are coupled with the coupling components in an acid medium, which may be buffered if desired.

The aminobenzothiazolesulfonic acid amides, which are employed in the form of their diazo compounds, are in part new. The process whereby they are obtained consists in reacting 1 mol of a compound of the formula II Z wherein R R R and R, possess the aforenamed meanings, with thiocyanic acid and cyclizing the resultant orthoaminothiocyanate.

A further process consists in reacting 1 mol of a compound of the formula Halogen0,8

the free amino group of which may be protected by a readily splittable acyl radical, with an amine of the formula followed where necessary by splitting off the acyl radical in the reaction product. Formation of this acid amide is effected preferably in presence of an acid-binding agent or with the aid of an excess of the amine When the acyl radical is present it can be split off in the normal way by partial hydrolysis, higher temperatures being most effective.

In some instances special conditions are necessary for cliazotizing the aminothiazole compounds. Some of them form very poorly soluble sulfates and therefore cannot be diazotized in concentrated sulfuric acid; Where this is the case, diazotization can be carried. out, for example, in phosphoric acid.

The azo dyestuffs of this invention which are employed as disperse dyestuifs are especially notable for their high brilliancy and very goodfastness to light, gas fumes, sublimation, pleating, washing, perspiration, water and sea water on secondary cellulose acetate, cellulose triacetate and polyester fibers. The dyeings are White dischargeable. The dyestuffs give a fairly good reserve of viscose, cotton and wool, especially when aftertreated with hydro-sulfites.

Those azo dyestuffs which are suitable for the spindyeing of acetate possess high fastness to light, washing, cross-dyeing, alkaline bleaching, gas fumes, oxalic acid, dry cleaning and peroxide bleaching. They also" show excellent fastness to sea water, perspiration, Water, soap baths, rubbing, decatizing and pressing.

In the following examples all parts and percentages are by weight and the temperatures are in degrees centigrade. The melting points are uncorrected.

EXAMPLE 1 12.1 parts of 2-aminobenzothiazole-6-sulfonic acidmethylamide are dissolved in 50 parts of 85% phosphoric acid at 20. After cooling to 5, 3.8 parts of sodium nitrite are added in the course of the next hour. Diazotization takes place very rapidly with precipitation of the diazo compound in the form of fine needles. In spite of vigorous agitation the resultant mass is of very thick consistency and it is advisable to dilute it with 40 parts of glacial acetic acid. On completion of diazotization a solution of 10.5 par-ts of N-hydroxyethyl- N-cyanoethylaminobenzene in 20 parts of glacial acetic acid is added to the mass. Formation of the dyestuflf follows in a short time and is accelerated by the addition of 50 parts of sodium acetate. After 30 minutes the thick mass is unloaded into 500 parts of water. The new dyestulf formed is filtered off, washed neutral with water and subsequently boiled in water to extract the small amount of unreacted starting product. Thus purified, the water-insoluble monoazo dyestuff dissolves in organic solvents to give brilliant red solutions. It corresponds to the formula CHa-NH-Oz CHQEGHQCCN CHrCHrQH shades which show good fastness to light, gas fumes, sublimation and wet treatments. The dyeings are readily dischargeable.

When N hydroxyethyl N cyanoethylaminobenzene is replaced by aliquot amounts of N-hydroxyethyl-N difluoroethylaminobenzene or 1 (N hydroxyethyl N- c'yanoethyD-amino-3-methylbenzene, similar dyestuffs are are obtained which show practically the same fastness to light. I

Again, by employing as coupling components 1-N.N- dihydroxyethylamino 3 methylbenzene, 1 N,N dihydroxyethylamino 3 acetylaminobenzene, 1 N.N -dihydroxyethylamino 3 acetylamino 6 methoxybenzene, 1 N.N diacetoxyethylamino 3 propionylaminobenzene, dyestuffs of rather more bluish shade are obtained, some of which are faster to washing than those previously described.

The diazo component used here is new. One meth-' od of producing it is as follows.

186 parts of l-aminobenzene-4-sulfonic acid-methylamide, melting point -11l (melting point of acetyl compound ISL-182), are dissolved in 1000 parts of 95% acetic acid, and 202 parts of 87.5% sodium thiocyanate added. To the clear solution at 7-l0 a mixture of'200 parts of bromine and 300 parts of 95 acetic acid is added dropwise. After two hours stirring the mixture is poured into 5 liters of water. The reaction mass is cooled and brought to pH 7.0 with caustic soda, after which it is stirred for 16 hours and then filtered. The filter residue is mixed with 1000 parts of 5% caustic soda and heated to 95 upon which the Z-aminobenzothiazole-G-sulfonic acidmethylamide formed goes into solution.

1 impurities are filtered off and on cooling the filtrate is neutralized, upon which the new Z-aminobenzothiazole- 6 sulfonic acid-methylarnide is precipitated. It is isolated by filtration and drying, and crystallizes from glacial acetic acid as colorless cubes with a melting point of 225. On analysis the following values are obtained:

.Actual, Calculated, Percent Percent EXAMPLE 2 When the 12.1 parts of 2-aminobenzothiazole-6-sulfonic acid-methylamide in Example 1 are replaced by 12.8 parts of Z-aminobenzothiazole-o-sulfo-nic acid dimethylamide (melting point. 230 a dyestufli is formed having the formula:

CHz-CHz-CN CHr-CHz-OH This dyestuff, which melts at 170, dyes acetate, triacetate and polyester fibers from aqueous dispersion in brilliant red-pink shades which are outstandingly fast to light, gas fumes, sublimation and pleating. The dyeiugs are dischargeable and the reserve of cotton, viscose rayon and wool is very good. The dyestuff has somewhat poorer light fastness onpolyamide fibers than on acetate.

A dyebath is prepared with 1 part of the abovedescribed dyestufi dispersed with the aid of Turkey red oil, 6 parts of a sulfonated fatty alcohol and 3000 parts of water. 100 parts of secondary cellulose acetate fabric are introduced into the bathiat roomtemperature; the temperature is.raised to in 1 hour and the bath maintained at this temperature for afurtheijhour. After The insoluble assumes 6 this time the dyeirigp'rocessfis completed and the matefas tness to light, washing, cross dyeing, alkaline chlorina nal is removed, rinsed and dried. tion, oxalic acid, peroxide, bleaching, gas fumes, dry

' To improve its dispersibility the dyestuff can be precleaning, and hydrosulfite.

viously ground with suitable wetting, dispersing or emulsifying agents, preferably in presence of inorganic salts, 5 EXAMPLE 4 for example Glaubers salt. Alternatively, it can be When the 12.1 parts of 2-aminobenzothiazole-6-sulfonic pasted with water, intimately mixed with a dispersing a id-met y i 0f EXamPIe 1 are replaced y Parts agent and then converted into a dyestutf powder by dryof Z-aminobenzothiazole-6-sulfonic acid-3'-methoxyproing unde suit ble ditio pylamide with melting point 126, a dyestufi is obtained Dyeing of rather more yellowish shade but of equally 10 of formula good fastness are obtained with the dyestuffs of the forwith a melting point at 103 and with similar dyeing CHa-CHg-CN CHr-CHr-OH mulae: properties. CH EXAMPLES 5 When the 12.1 parts of Z-aminobenzothiazole-6-sulfonic cm-crm acid-methylamide in Example 1 are replaced by 13.5 CH: 'C parts of 2-aminobenzothiazole-6-sulfonic acid-isopropylcm-cm-oH amide of melting point 212, a dycstutf is obtained of formula on, S 8

N-0r OH 1N-O1 CN=N N O-N=N N CHa 3 CH:

/ CHs-CHg-OH N/ CHs-CHa-OH It is interesting to note that'the dyestuffs of Examples 1 with snmlar dyemg propemes and meltmg Pomt 114 and 2 exhibit better building-up properties on cellulose EXAMPLE6 triacetate and polyester fibers, e.g. Dacron (registered When the 10.5 parts of N-hydroxyethyl-N-eyanoethyltrademark), than the analogous dyestuffs produced from aminobenzene of Examp 1 are replaced y p r 2amino-6-methylsulfonylbenzothiazole. of N-ethyl-N-cyanoethylaminobenzene, a dyestuff is obtained of formula EXAMPLE 3 V S When the 12.1 parts of Z-aminobenzothiazole-6-sulfonic 40 a a acid methylamide of Example 1 are replaced by 14.2 parts j V O of 2-amin0-benzothiaz0le-6-sulfonic acid-phenylamide (melting point 197), the resultant dyestufi has the 0 formula V with similar dyeing properties and melting point 145.

O CH Ora-"cs V V CHr-CHs-OH and a melting point at 140; It dyes acetate and triace- EXAMPLE 7 tate fibers from aqueous dispersion in brilliant pink-red wfi th 10,5 parts of N-hydroxyethyl-N-cyanoethyl- 811M163 of y good s- T ilmmlle-tioll.lbilit}!0'f r aminobenzene in Example 1 are replaced by 11.5 parts of the pure dyestulf is 40 grams per liter, a solubility which a N-acetoxyethyl-N-cyanoethylaminobenzene, a dyestutf is gives it good suitability for dyeing cellulose acetate in the obtained having the formula CHg-CHr-CN spinning solution. A suitable spin-dyeing procedure is as Its melting point is 149 and it has similar fastness properfollows. 7 ties to thepreviously described dyetufis with a shade of 100 parts of cellulose acetate are mixed fora short more yellowish hue. Due to the introductiomof the time with 300 parts of a mixture of solvents (93% acetone acetoxy radical the scarlet shades produced on triacetate and 7% methanol) and left overnight to swell, Next and polyester fibers show a further improvement in light day 1 part of the above dyestufi is dissolved in 60 parts fastness. of the same solvent mixture by simple shaking and the XAMP 8 soluiton added to the main solution. The whole. is stirred in an open mixing kettle until 60 parts of the e When the 12 1 parts of 2-am1n0benzoth1azole-6-sulfomc solvent have evaporated. The dyed mass is pumped into acld-mcthylamlfle 1n f l 1 are P F PY the spinning pot in the usual way and spun. The formed parts of Z-ammobenzothrazole--sulfomc acid-dimethylfilaments are of bright redshade and possess excellent 15 amide and at the same time the 10.5 parts of N-hydroxy- 7 ethyl-N-eyanoethylaminobenzene are replaced by 11.5 parts of N-acetoxyethyl-N-cyanoethylaminobenzene, a dyestufi is obtained of the formula. a

fied dichlorobenzene are added and heating continued to- 100", the bath'b'eing maintained at the boilfor 1 h'our.- After this time the dyed material is removed, rinsed with water and. dried. The scarlet" shade obtained is fast to CH3 8 5 light, washing, perspiration, cross dyeing, sea water, g oHi-oH cN fumes and heat setting. i

- In Table 1 below are listed further dyestufis with similara sortie 'nsm v cn qn f stnes pr pe s and 1 o e instances better light fastness. They correspond to the formula with melting point 180. It gives on acetate, triacetate CHrCI-Ia-CN a s and polyester fibers scarlet shades which have similar N-Oz fastness properties to those of the formerly described f C-N=N N\ /u dyestuffs. R GHz-CH Polyester fibers are dyed as follows: 7 a Y A dyebath is prepared with 1 part of the above de- Rt Table I Shadeon Example Ra R4 Ra Ra Y H w Second- No. y

Acetate 0H n n 'rr "H" CH3" H H H 11..... cm. rt 11 r-r H in cm H n "H R 0430-0113"... cm. H H H..- H H H OH. H. H CHFCHPOH H H n w 16 (JEz-CHg-OH..- 0H2-0H20H- H H H-.. H

17 OHr-OHPSLN CHa-CHz-O.... H H H.-." H

n rr H H 01---- Fr CH3; FT

BL-.. H-.-

H.-. CH3 CzH5. H. OCO-C'Ha pink. H cm H H H Do. OH=CH-OH=OH- H. OH... GHQ-OH red:

V10 6 0H=cH-0H=o11- w n "Ff Do. n H FT n H H w 11 ink. 11.. scarlet T-T H H H C2255" pink. H 7B H -CH3 CH; Do. H it" 11 n 1:: D Fr Fr .11"... H H Do. 11 II Fl' FT Fl GEL" n n "H" n F Do, 3-methy1-phenyL. -H F Gl.'.--- 1 O-CONH-CeH5. yellgw- Dink,

scribed dyestufi dispersed with the aid of Turkey red EXAMPLE 39 oil, 6 parts of a sulfonated fatty alcohol and 3000 parts w n the 5 0f y y h 1 0f Watef- Parts of Polyester fiber are aminobenzeneofExample 1 are replaeed by 14.5 .parts entered into this bath at room temperature and the .temof N N-bis-,(acetoxyethyl)-amin0benzene, a dyestufi is perature raised to 60 in 30 minutes. 15 parts of emulsiobtained which has the formula CHa-C Hz-O-C O-GHi and with a melting point at 156. Dyed at high temperatures from aqueous dispersion, preferably in presence ,7

of compounds with dispersing action, it produces on polyester, acetate and triacetate fibers brilliant pink-red and melts at 155". It dyes cellulose acetate and triacetate fibers and polyester fibers in yellowish pink shades of good all-round fastness. Similar fastness properties are shown by the dyestuif shades which possess very good fastness to light, wash- CH3 S ing, perspiration, cross dyeing, sea water, gas fumes, CHrOHr-O-CO-OH, sublimation and pleating. The dyeings are discharge- 0 C N=N able white, and the dyestuff reserves cotton and viscose. N// \CHrOHrO CO OHI The wool reserve s very good, especially when the m 1 blended yarn or fabric is treated after dyeing with sodiwhich melts at 153 um hydrosulfite. 0n acrylic fibers, e.g. Orlon (regis- In Table 2 further dyestuffs are listed which are suittered trade mark), only light shades can be obtained; able for dyeing polyester, acetate and triacetate fibers. however, they are outstandingly fast to light even in They have the formula: one-twenty-fifth of standard depth. V S z 11 'cm-cH-o-omom EXAMPLE 40 g a v R a CN=N N\ a. a When the 10.5 parts of N-hydroxyethyl-N-cyanoethyl- 7 oHroH-o-oo-om aminobenzene of Example 1 are replaced by 15 parts 20 Table 2 Shade on Example No. R; R Y Z u Secondary Acetate 41 OH. cm H H H ink.

42 on. an. on. H H luish ink.

4:4 on. H on. H H 550.

44 nn. H H H H ink.

45 PH, 0H. 0H. OCH; H iuish pink. pink.

46 cm on. H H OH: pink.

47 c 0H. cm on, H bluish 49 CH: CH1 NHCOOH3.---- E H Do.

51 CH cm H 11 Do.

52 cm H. H H Do.

53 cm on, H H Do.

54 0H on. H H Do.

57 CH pheny H H Do.

m 0.1 1. phenyl (1 H H scarlet.

61 CH: phenyl H H D0.

62 CHOH -OH phenyl H H D0.

63 F pheny H H. Do.

64 H cyolohexyL- H H D0.

65 H phenyl H CH3 11k.

68 H phony] Cl H CH1 yellowish 67 H na ghthyinu NH-COO9H19.. H H red-violet of 1-N.N-bis-(acetoxyethyl)-amino-3-chlorobenzene,' the resultant dyestufi has the formula CHg-CHz-O-C O-GH:

. .\f' L f ewe 14 The wet fastness properties of dyestufis of such large are suitable for coloring lacquer media, oils, synthetic molecular size are naturally superior to those of the resins and manufactured fibers in the mass. In the previously described dyestuffs, and with .some of them V formula shown Y, w and u represent preferably hydrogen the very highest fastness to boiling, cross dyeing and or methyl and v hydrogen, methyl, ethyl, cyano, hydroxy, saponification is obtained. The dyestufis enumerated in 5 acetoxy or the phenylcarbamic acid ester group. Espe- Table 5 are of special interest; they conform to the V cially worthy of note are the following dyestuffs:

' which dye cellulose acetate in the mass in brilliant, formula shown above and are characterized by the symfast-to-light red shades with very good wet fastness bo1sR,,R ,Y,u,vand w. properties. v

' Table 5 Example R: R4 Y u v w or H 0-OO-CH: o-co-cHr H phenylethyl. Cl H 0-00-0731 H. 3-hgdrolxymethyl- 01 H O-GO-CH:

GUY. a' nethylphenyl 01 H QC0NHC .H oc0NH-o.H

A number of the dyestufis of Examples 143 to 169 Formulae of representative dyestufis of the foregoing are readily soluble in acetone and dye fibers-notably 60 examples are as follows: cellulose acetatein the mass in brilliant, fast-,to-light 7, EXAMPLE 41 red shades. Those dyestuffs in which represents chlorine yield the most yellowish reds and are the fastest. 0H; S to gas fumes. VN OIS HrCHrO-CO-CH! Besides the dyestufis already namedfl e disaz'o y rm l Q stufis produced by coupling 2' moles of a 2-diazobenzo-, r v 1 thiazole-fi-sulfonic acid amide with .1 mol of an amine of the formula V EXAMPLE s1 CHrCHrO-CO-CH! s on on 0-00-01:

N O r I a.

/ CHrCHrO-CO-CH' J V I I NH-CO-Ci a Having thus disclosed the invention, what We claim is: 1 with at most 18 carbon atoms, 1. A azo ,dyestufi which corresponds to the formula M represents a member selected from the group consisting of hydrogen, hydroxyl, lower alkoXy, 'acetoxy and S H 2 lower carbamic acid alkyl ester, when n stands for the figure 1, and a simple C-N linkage when n stands t C'N=N N forgthe figure 2,

l H A a- J Z represents a member selected from the group consisting Ra n of hydrogen, methyl, methoxy and, together with NCH --R and the adjacent benzene nucleus, a tetrahydroquinoline ring, and R represents an alkylene hydrocarbon radical with 1 to 4 n repr One Of the integers 1 and carbon atoms, .2. The monoazo dyestulf oflhe formula wherein S CHa-CHr-O-C 0-011:

R represents a member selected from the group consist- 3. The monoazo dyestufi of the formula ing of lower hydroxyalkyl, lower dihydroxyalkyl, lower 1 alkoxyalkyl, lower cyanoalkyl, lower acetoxyalkyl, g s

lower propionyloxyalkyl, polyfluoromethyl, fluorinated N-O OHrOHrO'CO'CH lower cyanoalkyl, lower carbalkoxyalkyl and lower V O' carbamic acid alkyl ester, N// g og brcbsg R represents a-member selected from the group consisting of hydrogen, lower alkyl, lower hydroxyalkyl and 4. The monoaz o dyestuff of the formula lower alkoxyalkyl,

5. The. monoazo dyestufi of theformula R represents a member selected'from the group consist- 7 ing of hydrogen, lower alkyl, lower hydroxyalkyl, E 7 s p lower alkoxyalkyl, phenyl, methylphenyl, naphthyl, 5o N-OQ'S- I hydroxymethylphenyl, cyclohexyl, benzyl and phenyl- Q CN=N I ethyl, N// 'CHFOHFOIOO'iJ H: R represents a member selected from the group conslstj ing of hydrogen, lower alkyl and, together with R 1 H 6. The monoazo-dyestnfi of the formula ---CH=CH--CH=CH---, R represents a memberselected from the group consist- V I ing of hydrogen, lower alkyl and, together with R 7 s CHn-CHg Y represents a member selected from the group consisting C'HFCHF-ON of hydrogen, chlorine, bromine, lower alkyl, lower 8 alkoxy, trifluoromethyl, trifluoroacetyl, alkanoylamino 0 References Cited in the file of this patent" UNITED STATES PATENTS 2,149,051 Helberger et a1. Feb. 28, 1939 2,785,157 Straley'et a1 M'ar.12, 1957 2,832,761 Straley et a1. Apry29, 1958 2,889,315 Bossard et al. June 2, 195.9

UNITED STATES PATENT OFFICE CERTIFICATION OF CORRECTION Patent 2,980,666 April 18, I961 Ernest Merian et a1.

It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

I Column 2, line 45, for "X" read Z column 5, line 1O for "Dyeing" read -Dyeings line 71, for "-soluiton" read solution column 6, EXAMPLE 5, the left-hand portion of the formula should appear as shown below instead of as in the patent:

column 16, claim 3', the lower right=hand portion of the formula should appear as shown below instead of as in the patent:

Signed and sealed this 28th day of November 1961.

(SEAL) Attest:

ERNEST W. SWIDER DAVID L. LADD Attesting Officer Commissioner of Patents 

1. A AZO DYESTUFF WHICH CORRESPONDS TO THE FORMULA 